A victory against Sunderland today would put Gunners within a point of leaders.
Arsenal must pounce on Manchester United slip
Wenger said his "obsession" is beating Sunderland at Emirates Stadium today after United's midweek loss at Chelsea left the Gunners four points behind with a game in hand.
Victory against the Black Cats would amplify pressure on Sir Alex Ferguson's United side, who travel to Liverpool tomorrow.
Ferguson has appealed against the charge of improper conduct by the Football Association. He had criticised match official Martin Atkinson's performance in United's 2-1 defeat to Chelsea on Tuesday, saying his team didn't get a "fair or strong referee."
Ferguson has requested a personal hearing, which will take place no later than March 25.
Wenger wants his players to put Tuesday night's eagerly awaited Champions League last-16 second-leg showdown with Barcelona out of their minds and concentrate on domestic issues.
"The championship is very important. Personally, I cannot believe we play Barcelona next week because my obsession is really Sunderland," he said. "The obsession is more than the Champions League because for me it's highly important that we take advantage of our situation in the Premier League.
"We battled everywhere since the start of the season against many specialist opinions that we have no chance at all.
"Now that we are in this situation, it would be very dramatic if we would not consider the importance of the game tomorrow."
The midfielders Cesc Fabregas and Alex Song will miss the Sunderland game and face a race to be fit for Barcelona.
"They are still improving for the Barcelona game. They have a chance," Wenger said. "Fabregas at the moment has a stronger chance than Song, but they have a chance."
Aaron Ramsey is included in the squad and could make his first Arsenal appearance since suffering a broken leg at Stoke in February of last year.
Steve Bruce, the Sunderland manager, has injury problems of his own; he is set to be without eight first-team regulars for the trip to London today.
The Black Cats have been without the likes of Michael Turner, Lee Cattermole, David Meyler, Fraizer Campbell and Danny Welbeck for months, and with Nedum Onuoha and Bolo Zenden having joined them on the casualty list and the goalkeeper Craig Gordon heading for Sweden tomorrow to consult a specialist over his niggling knee problem on, the manager's options are limited.
Said Bruce: "I don't think I have been involved in anything like now when we have got nine [injured], and probably six of them have been out for three months or more, and some of them have been out for six months, which is cruel, it really, really is."
7pm, Abu Dhabi Sports 3 & 5